Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005120)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(296867);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/27");

  script_cve_id("CVE-2024-49878");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005120)");

  script_set_attribute(attribute:"synopsis", value:
"The Unity Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the
UTSA-2026-005120 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    resource: fix region_intersects() vs add_memory_driver_managed()

    On a system with CXL memory, the resource tree (/proc/iomem) related to
    CXL memory may look like something as follows.

    490000000-50fffffff : CXL Window 0
      490000000-50fffffff : region0
        490000000-50fffffff : dax0.0
          490000000-50fffffff : System RAM (kmem)

    Because drivers/dax/kmem.c calls add_memory_driver_managed() during
    onlining CXL memory, which makes System RAM (kmem) a descendant of CXL
    Window X.  This confuses region_intersects(), which expects all System
    RAM resources to be at the top level of iomem_resource.  This can lead to
    bugs.

    For example, when the following command line is executed to write some
    memory in CXL memory range via /dev/mem,

     $ dd if=data of=/dev/mem bs=$((1 << 10)) seek=$((0x490000000 >> 10)) count=1
     dd: error writing '/dev/mem': Bad address
     1+0 records in
     0+0 records out
     0 bytes copied, 0.0283507 s, 0.0 kB/s

    the command fails as expected.  However, the error code is wrong.  It
    should be Operation not permitted instead of Bad address.  More
    seriously, the /dev/mem permission checking in devmem_is_allowed() passes
    incorrectly.  Although the accessing is prevented later because ioremap()
    isn't allowed to map system RAM, it is a potential security issue.  During
    command executing, the following warning is reported in the kernel log for
    calling ioremap() on system RAM.

     ioremap on RAM at 0x0000000490000000 - 0x0000000490000fff
     WARNING: CPU: 2 PID: 416 at arch/x86/mm/ioremap.c:216 __ioremap_caller.constprop.0+0x131/0x35d
     Call Trace:
      memremap+0xcb/0x184
      xlate_dev_mem_ptr+0x25/0x2f
      write_mem+0x94/0xfb
      vfs_write+0x128/0x26d
      ksys_write+0xac/0xfe
      do_syscall_64+0x9a/0xfd
      entry_SYSCALL_64_after_hwframe+0x4b/0x53

    The details of command execution process are as follows.  In the above
    resource tree, System RAM is a descendant of CXL Window 0 instead of a
    top level resource.  So, region_intersects() will report no System RAM
    resources in the CXL memory region incorrectly, because it only checks the
    top level resources.  Consequently, devmem_is_allowed() will return 1
    (allow access via /dev/mem) for CXL memory region incorrectly.
    Fortunately, ioremap() doesn't allow to map System RAM and reject the
    access.

    So, region_intersects() needs to be fixed to work correctly with the
    resource tree with System RAM not at top level as above.  To fix it, if
    we found a unmatched resource in the top level, we will continue to search
    matched resources in its descendant resources.  So, we will not miss any
    matched resources in resource tree anymore.

    In the new implementation, an example resource tree

    |------------- CXL Window 0 ------------|
    |-- System RAM --|

    will behave similar as the following fake resource tree for
    region_intersects(, IORESOURCE_SYSTEM_RAM, ),

    |-- System RAM --||-- CXL Window 0a --|

    Where CXL Window 0a is part of the original CXL Window 0 that
    isn't covered by System RAM.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://src.uniontech.com/#/security_advisory_detail?utsa_id=UTSA-2026-005120
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a9374101");
  # https://lore.kernel.org/linux-cve-announce/2024102115-CVE-2024-49878-8099@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d121abcb");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2024-49878");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2024-49878");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2024/10/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Unity Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/UOS-Server/release", "Host/UOS-Server/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'UOS Server' >!< os_product) audit(AUDIT_OS_NOT, 'UOS Server');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'UOS Server');
if (! preg(pattern:"^20.1050e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050e', 'UOS Server ' + os_version);

if (!get_kb_item('Host/UOS-Server/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'amd64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}


if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'kernel');
}